Typically, locomotive engines operate on liquid fuel, such as diesel. However, with the developments in technology, the locomotive engines are capable of operating on gaseous fuel, such as natural gas. A fuel supply system of a locomotive engine includes a valve assembly to control flow of pressurized gaseous fuel from a fuel tank to the locomotive engine. Conventionally, a pneumatic system is used to displace a valve element of the valve assembly from a rest position of the valve element. In a displaced position, the valve element allows flow of the gaseous fuel to the locomotive engine, through the valve assembly.
However, flow of the pressurized gaseous fuel poses a risk, which may affect operation of the fuel supply system. For example, the pressurized gaseous fuel may leak from an actual flow path defined within the valve assembly and enter into a chamber where air is supplied. Such leakage of the gaseous fuel into the chamber may render components of the pneumatic system non-functional, thereby affecting operation of the locomotive engine.